Soak the rice in water beforehand or use it directly.

Remove the stem of the shiitake mushroom and slice half into strips and the other half into small cubes.

Heat a cast iron pot over medium heat and add cooking oil. Stir-fry the shiitake mushroom and onion.

Remove the sliced shiitake mushroom once the onion is cooked and set aside for garnish.

Add the soaked rice to the pot and pour water in a 1:1 ratio with the rice.

Season with soy sauce, adjusting the amount to taste.

Stir occasionally with a wooden spatula and cook uncovered until most of the water evaporates.

Place the reserved shiitake mushroom slices on top and cook on low heat for 2 minutes with the lid on.

Turn off the heat and let the rice sit for 5 minutes to steam.